-3x – 4y = 20
x - 10y = 16
if (x, y) is the solution to the system of equations
above, what is the value of x ?
a) - 14
b) -12
c) -4
d) 16

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15